Hair rollers can consist of a roller core, comprising openings allowing the moisture still present in the hair after washing to escape, and a selfgripping fabric tape attached thereto. The reverse side of the selfgripping fabric tape also comprises openings for the same reason, these being formed by a mesh-type web structure.
In hairdressing technology many types of hair rollers are known, which are used to roll up mainly female hair to produce curls. Such hair rollers are well known as curlers.
The technique of rolling up hair is not without problems as the hair tends to slip on a smooth roller. In addition, the hair must be tautly fastened to the hair roller for a certain length of time to ensure that curls will form.
Numerous types of hair rollers have been developed in order to simplify the rolling technique, all of which aim at facilitating initial binding of the hair to the hair roller.
Thus, for example, bundles of bristles in the shape of round brushes can be inserted into the core of the hair roller, the bristles then passing through the open web structure of the hair roller wall to form a brush-like surface on the hair roller. With bristles, the hair binds more easily at the outset, thus facilitating taut rolling. The same purpose is served by injection-molded rollers featuring plastic bristles on their surfaces.
With all above described hair rollers it is necessary to fasten the hair roll by means of clips, grips or pins after rolling. Such an operation requires dexterity and training, which is, of course, available at an adequately professional level in hairdressing salons.
An increasing number of women are, however, tending to curl their hair themselves in order to save the time-consuming and expensive trip to the hairdressing salon. Since the talent of the home hairdresser is naturally inferior to that of the professional stylist and there is usually no second person available to help, the technical demands on a hair roller for home use are therefore very much higher than on those hair rollers used in a professional environment.
This objective is fulfilled by selfgripping hair rollers on the basis of selfgripping fabric tapes.
Selfgripping fabric tape is widely known as a fastening system in the clothing trade, usually referred to as hook-and-loop fastening tape. In that particular application two tapes are used, namely one with numerous hooks and the other with as many loops on the surface. When the two tapes are brought together under application of slight pressure, they immediately engage and form a very firm fastening. The material of these extensively used selfgripping fabric tapes is usually synthetic, more specifically on the basis of polyamides such as nylon.
In the selfgripping hair roller only one layer of self-gripping fabric tape is necessary. The construction of the tape is modified such that the hooks are longer in order to exert an adequate binding effect on the rolled lock of hair and still to provide a sufficient binding effect for longer hair and thicker locks of hair. The rows of hooks are also connected by an open nylon mesh made of webbing through which the hot air of the hair dryer can easily pass.
The hair roller itself is well ventilated by openings in its outer sleeve.
The selfgripping fabric tape is permanently fastened to the roller core that usually also consists of plastic.
These hair rollers have achieved an exceptional degree of success, not only in the market for home hairdressing but also in hairdressing salons, and now have considerable market potential.
They simplify initial binding of the hair at the start of rolling, permit taut rolling, and require no pins, grips or clips. On completion of the rolling operation they hold the hair roll firmly in place without any additional means. In this procedure it is important that the self-gripping fabric tape tautly surround the roller core, does not have any folds and does not slip on the roller core.
However, such hair rollers have the disadvantage of being exceptionally expensive. This is due partly to the high price of the selfgripping fabric tape and partly to the still largely manual production technique.
Polypropylene has proved a very suitable and also inexpensive material for the roller core. The selfgripping fabric tape is wound round this roller core, which is available in up to 15 different diameters, and the ends heat welded together with a small overlap. The welding of nylon to nylon does not fuse with the polypropylene roller core lying underneath, so that the tape lies loosely on the core. Since the selfgripping fabric tape is not initially fixed at the start of winding around the core, it is often very loosely wound and tends to form folds during the hair rolling operation.
Many attempts have been made to remedy these deficiencies. The welding seam, for instance, has been executed to a depth at which the plastic material of the core below also melts, resulting in a flow of material into the selfgripping nylon tape, thus giving the latter a certain mechanical anchorage.
In many cases, however, the nylon tape then becomes so thin that it will easily break. In addition, such a weld seam is very ugly in appearance and often has fused hard ends projecting beyond the edge of the roller. Another disadvantage of this process is that only a small segment of approximately 5.degree. of the circumference of the hair roller is firmly connected, the remaining 355.degree. resting loosely on the roller core.